As demand for RF bandwidth increases, we see great potential in free space optical (FSO) communications. However fading due to small variations in the atmosphere's refractive index, plus the effects of cloud and fog, may cause large performance degradation in current FSO links. Modern channel coding methods, plus the use of MIMO and hybrid FSO/RF techniques, can provide huge improvements in performance.
In 2009 we started a new project in this area supported by the Sir Ross and Sir Keith Smith Fund and Cisco Systems, plus travel funding from the Royal Society. This project has derived new bounds on the capacity of FSO and hybrid FSO/RF systems, is measuring joint FSO and RF channel characteristics over a 12 km test range and has designed and tested an LDPC-based FSO transmission system. In these tasks we are currently collaborating with researchers in Cambridge University, the Australian Defence Science and Technology Organisation (DSTO) and the German Aerospace Agency (DLR). We would like to hear from companies that are interested in FSO communications.
ITR has been involved in a high-speed WLAN project called GLIMMR (Gigabit Low-cost Integrated Millimetre-Wave Radio) funded by the ARC. The overall aim of this project is to demonstrate a low-cost system-on-chip, with associated antennas, for commercial applications in the 60 GHz ISM band. Three universities are involved in GLIMMR - Macquarie, Adelaide and UniSA - and the industry partner is NHEW R&D. These notes illustrate some recent channel measurements from the GLIMMR project using the second GLIMMR Test Chip.
ITR has recently completed an ARC Linkage Grant to continue the
development of very high-rate remote sensing demodulators with Dutch industry
partner Satellite Services
BV. ITR has previously worked with SSBV on the successful ERSDEM 2.5
project. For more information on ERSDEMs see
this
example and the SSBV web site.
We are continuing a study into intersatellite links (ISLs). The aim of the project is to explore what could be achieved in a low-cost ISL payload on LEO satellites using modern approaches to modulation, coding and multiple access. We assume an 'ad hoc' constellation of satellites where the ISL hardware is carried as a secondary payload. Here are some short animations showing these ISLs. This project is sponsored by Cisco Systems who are keen to develop new approaches to satellites networks.
ITR has also been working with the Electronics and Telecommunications Research Institute (ETRI) in South Korea on new techniques for satellite communications.
We have recently carried out a small project for DSTO using acoustic beamforming techniques to separate overlapping speech signals. This page provides some audio samples from the initial project.
The University of SA was heavily involved in the SSP04 program held in Adelaide by the International Space University (ISU). 114 graduate students visited Adelaide during July and August 2004 for this SSP. ITR was particularly involved in two areas:
Assistance with a Team Project aimed at improved broadband communications for remote and rural communities in Australia. Here is the Executive Summary. Please contact the ISU obtain a copy of the full report (133 pages).
Supervision of ISU students working on a sounding rocket project. Two Zuni rockets were launched from Woomera in August with the assistance of ASRI. One of the payload experiments included a telemetry downlink - here's a copy of the SSP student presentation on this project. You might also be interested in the video from an on-board camera.
More recently, we supported SSP05 and SSP06 (held in Vancouver and Strasbourg respectively). Bill Cowley was the "Satellite Applications" CoChair during the first half of these SSPs, and helped for 1 week during the SSP07 in Beijing.
In Australia the current cost of two-way satellite communications is much greater that terrestrial alternatives such as ADSL and cable. ITR believes that the use of modern transmission and networking techniques, combined with bandwidth aggregation through a single earth terminal for each small community, could bring about a substantial reduction in the cost of broadband for remote communities.
We submitted a short outline proposal regarding these ideas to the Australian Broadband Advisory Group inquiry in 2002. This work is continued in the ITR SNAP project and also in the SSP04 Team Project mentioned above.
This CRC ran from 1998 to 2005 and was responsible for Australia's second satellite, "FedSat". For more detail, see our CRCSS pages.